Life getting in the way of blogging... a tragedy I know!
I thought I would share an update on the research that I'm doing at school which is pertinent to the topic at hand. We're investigating gas storage capabilities of metal-organic frameworks. For those of you who don't have the benefit of a PhD to explain this stuff so you sound smart, these are low density (not a lot of material in a particular space) solids (crystals) which allow other molecules to reside inside of them. Think Fisher Price Construx or a building without walls, just the iron framework.
The organic ligands (or beams) can be almost anything with diametrically opposed (located on the two opposite ends) metal-grabbing groups (like an acid). In our case, they are one benzene ring (very common organic structure) with two carboxylic acids on either end (like citric acid, nothing too scary) and one amino group (a basic functional group found in proteins). The connectors (clusters at the corners) are zinc atoms surrounding one oxygen atom. This is what they look like at an atomic level. Cluster to cluster is about 12 angstroms or 1.2 x 10^(-9)m (1/1000th of the width of a human hair).
I know the perspective is messed up but here is the same thing in color. Keep in mind that these are CUBIC crystals so each ligand (beam) is perpendicular or parallel to all the others.
Grey is carbon, blue is nitrogen (or possibly a nitrogen... there is only one per ring), red is oxygen and green is zinc. Here are the clusters up close:
The theory is this: many kilograms of these crystals are put into a container (not pressurized). When empty, the tank is cooled slightly and hydrogen is pumped in. The crystals take on the hydrogen like a sponge would take on water. No chemical bonds are changed, no structures are affected and nothing crazy has been done. After the tank is full, it can return to room temperature, totally saturated with hydrogen. While the vehicle (or power plant or lawnmower or whatever) is running, the tank is heated gently to create a positive (low) pressure of hydrogen to ensure a constant supply. The tank can be bumped, shot, breeched, even burned and there would be no explosion or additional fire because the hydrogen is locked into this matrix.
If this doesn't blow your mind something is wrong.
Thursday, August 30, 2007
Life getting in the way of blogging... a tragedy I know!
Tuesday, August 28, 2007
This is the much-delayed response to the article I posted a week or more ago written by the former GM exec who said that raised CAFE standard (i.e. industry-wide increases in MPG) takes too much money, technology and time. Here are several options the automakers can do to raise fuel efficiency without major R&D:
Lose weight, drag, RPMs and running time.
"We need solutions for the next 20 years, not just dreams," [Axel] Friedrich told the Journal. And to prove his point he hired a group of university engineers who managed to reduce the carbon emissions (and therefore improve gas mileage) of a regular VW Golf (aka Rabbit) by 25 percent using existing materials and technologies. Most of the changes made by Friedrich's engineers are straight out of Auto Engineering 101: reducing weight (lighter seats and carbon fiber hood) aerodynamic drag (substituting tiny cameras for side mirrors) and mechanical drag (fitting low rolling resistance tires). The team also installed longer ratios in the transmission to reduce engine revs at cruising speed, and put a gearshift indicator in the cabin to show the most efficient time to shift gears.The highest-tech change made by the team was to modify the Golf's engine so it stopped when the car was halted, and started when the driver depressed the gas pedal to move off. But even this is hardly cutting edge technology -- I can remember driving a prototype Golf fitted with a similar system developed by VW's own engineers at least 15 years ago.
Reduce friction and resistance; increase aerodynamics, gearing and induction.
Called the [Volvo] C30 Efficiency, this special car will sip diesel fuel at the rate of 4.5L per every 100 kilometers. That's 52.26 mpg to us Yanks. It achieves these numbers using a variety of techniques. For the engine, efficiency was increased by using low-friction transmission oil and optimizing the engine management software. An age old trick for good gas mileage, higher gearing, was used on 3rd, 4th and 5th gears to eek out a few more kilometers, as well. Low rolling resistance tires, another common strategy for higher mileage, were also used. Finally, Volvo made the C30 slipperier through the air by reducing its ride height, adding a special rear roof spoiler, new rear bumper, and even adding underbody panels to smooth out the car's belly. Even the new 16-inch rims are aero-optimized! The C30 Efficiency's engine is a 1.6L turbodiesel producing 105 hp. Not only does it achieve 52.26 mpg, but it also emits less than 120g of CO2 per kilometer.
Optimize navigation software for fuel consumption, teach people how to drive and assist the alternator (which, in turn, lowers engine loads) with electricity care of a mild hybrid regen system.
"the driver himself retains a major responsibility for a driving style that contributes to reduced fuel consumption. Individual driving style can reduce fuel consumption, and with it emissions, by up to 30 percent — without compromising on speed and dynamism." ...Audi's new nav system is said to incorporate "consumption-relevant data" and give route recommendations based on that information. "The necessary information about road conditions or traffic lights will be available with the next generation of digital road maps," Audi said. "Here, many Audi TDI and TSFI engines are equipped with an innovative energy management system, which uses the coasting and braking phases to generate and store electrical energy," it said. "At a standstill and when accelerating, this energy can be used to relieve the load on the alternator and the vehicle electrical system. Moreover, a new generation of start/stop systems is being developed."
Like Spaulding said, it isn't rocket science
Monday, August 27, 2007
Can you think of a device with a better name than the Sun Cracker? Better yet, the Solar Water Cracker!
The CHP cracker would use a parabolic solar dish to concentrate sunlight on a thermal reactor where water would be dissociated. The resulting hydrogen and oxygen would be filtered out, with the hydrogen sent off to a fuel cell to allow it to combine with oxygen in the air and make electricity. The temperature in the Solar Water Cracker furnace can reach 2200 C (3990 F) with a solar energy to electricity conversion rate (via the fuel cell) of 44 percent.
Wait a sec... that's not bad at all! Current solar technology gets about 10% conversion efficiency(if I recall correctly). Think about that in terms of transportation: you could have solar panels all over your roof for solar energy or a parabolic dish less than a quarter of the size. Either one could provide the energy to power your car (or home or whatever).
If your having trouble with the concept, imagine a satellite dish (like a dish network dish). The dish directs incoming signals (very weak, dispersed signals) towards the little arm that is centered in the middle. It's all geometry and trigonometry (fairly simple... relatively). You're basically concentrating a bunch of weak signals (or, in this case, weak energy). For sunlight, you simply need to reflect the light towards a common collector. On a BIG scale, it looks like this collector (which uses the heat to melt salt):